Ruben Fragoso, M.D., Ph.D.


To see if Ruben Fragoso is accepting new patients, or for assistance finding a UC Davis doctor, please call 800-2-UCDAVIS (800-282-3284).



Radiation Oncology

Locations and Contact

UC Davis Comprehensive Cancer Center

UC Davis Comprehensive Cancer Center
4501 X St.
Sacramento, CA 95817

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Additional Numbers

Clinic Phone


Clinic Fax


Clinic Referral Phone


Physician Referrals

800-4-UCDAVIS (800-482-3284)

Philosophy of Care

Undergoing radiation treatments can be scary and overwhelming. Each patient has a unique situation involving their specific diagnosis and the treatment of their disease. It is important to recognize the patient’s unique issues in order to provide care for the patient as a whole person. It is also important to help patients understand their diagnosis so that they can make more informed decisions and understand their care.

Clinical Interests

Dr. Fragoso's main clinical activities involve the treatment of both benign and malignant central nervous tumors that can arise in the adult and pediatric populations. Radiation treatment techniques include Gamma Knife radiosurgery and fractionated radiation radiotherapy (3D or IMRT). Medical interests revolve around the better understanding of gliomas, particularly high grade gliomas.

Glioblastoma multiforme (GBM), a WHO grade IV glioma, carries a poor prognosis for which there have been modest therapeutic advances. My area of interest and research is focused on targeting specific cancer cells that are thought to perpetuate the tumor within the GBM itself. These “cancer stem cells” tend to be resistant to treatment. We are studying ways in which these cells can be targeted specifically and destroyed.


Radiation Oncology

Center/Program Affiliation

UC Davis Comprehensive Cancer Center

Undergraduate School

B.A., Molecular Biology, Princeton University, Princeton NJ 1992

Medical School

M.D., Harvard Medical School, Boston MA 2004

Other School

Ph.D., Harvard Medical School, Boston MA 2004


Internal Medicine, Morristown Memorial Hospital, Morristown NJ 2005


Radiation Oncology, Thomas Jefferson University, Philadelphia PA 2009

Chen H, Nguyen KNB, Huang H, Feng C, Zhao X, Daly ME, Rao S, Fragoso R, Valicenti R, Sekhon S, Navarro SM, Kim EJ, Cho M, Tam K, Farkas L, Halabi WJ, Monjazeb AM, Rong Y. Effect and Safety of Radiation Therapy Boost to Extramesorectal Lymph Nodes in Rectal Cancer. Pract Radiat Oncol. 2020 Sep-Oct;10(5):e372-e377. doi:10.1016/j.prro.2019.12.007. Epub 2019 Dec 20. PMID:31866577.

Xie B, Zhang L, Hu W, Fan M, Jiang N, Duan Y, Jing D, Xiao W, Fragoso RC, Lam KS, Sun LQ, Li JJ. Dual blockage of STAT3 and ERK1/2 eliminates radioresistant GBM cells. Redox Biol. 2019 Jun;24:101189. doi:10.1016/j.redox.2019.101189. Epub 2019 Apr 9. PMID:30986607.

Goodarzi A, Thaci B, Toussi A, Karnati T, Kim K, Fragoso R. Glioblastoma Multiforme of the Conus Medullaris - Management Strategies and Complications. World Neurosurg. 2019 Jan 10:S1878-8750(19)30032-4. doi:10.1016/j.wneu.2018.12.164. Epub ahead of print. PMID:30639501.

McGee HM, Daly ME, Azghadi S, Stewart SL, Oesterich L, Schlom J, Donahue R, Schoenfeld JD, Chen Q, Rao S, Fragoso RC, Valicenti RK, Canter RJ, Maverakis EM, Murphy WJ, Kelly K, Monjazeb AM. Stereotactic Ablative Radiation Therapy Induces Systemic Differences in Peripheral Blood Immunophenotype Dependent on Irradiated Site. Int J Radiat Oncol Biol Phys. 2018 Aug 1;101(5):1259-1270. doi:10.1016/j.ijrobp.2018.04.038. Epub 2018 Apr 22. PMID:29891204.

Hartl BA, Ma HSW, Sridharan S, Hansen KS, Kent MS, Gorin F, Fragoso RC, Marcu L. Label-free fluorescence lifetime spectroscopy detects radiation-induced necrotic changes in live brain in real-time. Biomed Opt Express. 2018 Jul 5;9(8):3559-3580. doi:10.1364/BOE.9.003559. eCollection 2018 Aug 1. PMID:30338140.

Hegde JV, Shaverdian N, Daly ME, Felix C, Wong DL, Rosove MH, Garst JH, Wang PC, Veruttipong D, Rao S, Fragoso RC, Riess JW, Steinberg ML, Chen AM. Patient-reported quality-of-life outcomes after de-escalated chemoradiation for human papillomavirus-positive oropharyngeal carcinoma: Findings from a phase 2 trial. Cancer. 2018 Feb 1;124(3):521-529. doi:10.1002/cncr.30954. Epub 2017 Oct 17. PMID:29044458.

Yuan Z, Nair CK, Benedict SH, Valicenti RK, Rao S, Fragoso RC, Wright C, Qiu J, Rong Y. Converting Treatment Plans From Helical Tomotherapy to L-Shape Linac: Clinical Workflow and Dosimetric Evaluation. Technol Cancer Res Treat. 2018 Jan 1;17:1533033818785279. doi:10.1177/1533033818785279. PMID:29986638.

Hartl BA, Ma HSW, Hansen KS, Perks J, Kent MS, Fragoso RC, Marcu L. The effect of radiation dose on the onset and progression of radiation-induced brain necrosis in the rat model. Int J Radiat Biol. 2017 Jul;93(7):676-682. doi:10.1080/09553002.2017.1297902. Epub 2017 Mar 17. PMID:28306402.

Ames E, Canter RJ, Grossenbacher SK, Mac S, Chen M, Smith RC, Hagino T, Perez-Cunningham J, Sckisel GD, Urayama S, Monjazeb AM, Fragoso RC, Sayers TJ, Murphy WJ. NK Cells Preferentially Target Tumor Cells with a Cancer Stem Cell Phenotype. J Immunol. 2015 Oct 15;195(8):4010-9. doi:10.4049/jimmunol.1500447. Epub 2015 Sep 11. PMID:26363055.